New York Governor Andrew Cuomo said on Thursday he wants the state to raise its minimum wage over the next six years to $15 an hour, the highest of any U.S. state.

The proposal calls for the minimum wage in New York City to rise to $15 an hour at the end of 2018 and take effect statewide in July 2021, mirroring a state order signed on Thursday that applies only to the fast-food industry.

It would mark a significant hike from New York state’s current hourly minimum wage of $8.75, which will increase to $9 an hour on Dec. 31, and faced immediate opposition from business groups that called the hike unrealistic.

In contrast with the fast-food increase, which the Democratic governor said could be ordered by the state labor commissioner without legislative approval, Cuomo will need lawmakers’ approval for a hike for all industries.

A Cuomo proposal for a more modest minimum-wage increase was opposed by the Republican-led state Senate earlier this year.

Democratic politicians across the United States have made raising minimum wages a top issue over the past few years, but the most dramatic moves have come at the city level.

The Seattle suburb of SeaTac has raised the minimum wage for certain workers to $15 and Los Angeles plans to adopt the $15 an hour minimum by 2020. A ballot measure in the District of Columbia to raise the minimum wage to $15 an hour is expected to go before voters next year.

Some business groups said Cuomo’s proposed hike was too aggressive.

“A precipitous increase that threatens the most vulnerable businesses and employees would not find a lot of supporters in the business community,” said Kathryn Wylde, president of the Partnership for New York City.

Cuomo contended the hike would boost the state’s economy.

“The families that get that money are going to spend that money,” he told a labor rally in New York City.

New York State Labor Commissioner Mario Musolino on Thursday signed the order making the statewide $15 minimum wage for fast-food workers official following a recommendation by the New York Wage Board in July.

Washington state currently has the highest statewide minimum wage, at $9.47, according to the National Conference of State Legislatures. Massachusetts is set to hike its minimum to $11 in 2017.